A liquid crystal display device includes a substrate (hereinafter referred to as a “TFT substrate”) on which a plurality of pixels each including a switching element constituted of a thin film transistor (hereinafter referred to as a “TFT”) are formed, an opposite substrate disposed opposite to the TFT substrate, and a liquid crystal layer interposed between these substrates. Liquid crystal display devices display images by controlling the light transmittance through liquid crystal by applying a voltage corresponding to an image signal (hereinafter referred to as a “signal voltage”) to a pixel electrode formed for each pixel, and applying a common voltage (also referred to as a “common signal”) to a common electrode formed on the opposite substrate.
The common signal is supplied from an external source to common transfer electrodes on the TFT substrate through wiring lines (hereinafter referred to as “common signal lines”) formed on the TFT substrate. The common transfer electrodes are electrically connected to the common electrode on the opposite substrate, and thus, the common signal is further supplied to the common electrode.
However, because the common electrode is made of a transparent conductive film such as ITO (indium tin oxide), the resistance thereof is high. As a result, the lag of the common signal varies depending on the position on the common electrode, which increases the susceptibility of the image displayed in the liquid crystal display device to display unevenness. Also, the load on the common signal line becomes high, increasing the likelihood of shadowing in the image. Liquid crystal display devices with a large display are particularly susceptible to these phenomena.
Increasing the number of common transfer electrodes disposed on the TFT substrate and reducing the connecting resistance between the common electrode and the common signal line is effective in order to reduce display unevenness in the image by decreasing variation in common signal lag depending on the position on the common electrode, and to reduce the occurrence of shadowing by decreasing the load on the common signal lines. Patent Document 1 discloses a configuration in which a plurality of gate drivers and a plurality of source drivers are disposed in order to increase the number of common transfer electrodes, and common transfer electrodes are formed in the spaces between adjacent gate drivers and source drivers.